Dental chair.



F. BITTER, DECD.

A. R. SHUMWAY & L. A. RITTER. EXECUTORS.

DENTAL CHAIR.

APPLICATION FILED MAY 16. I912.

' Patented Nov. 9, 1915.

Patented Nov. 9, 1915.

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DENTAL CHAIR.

APPLICATION FILED MAY I6, 1912.

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FRANK BITTER, OF ROCHESTER, NEW YORK; ADELINA BITTER SHUMWAY AND LAURA A. BITTER EXEGUTOBS OF SAID FRANK BITTER, DECEASED.

DENTAL CHAIR.

Application filed May 16, 1912.

To aZZ whom it may concern:

7 Be it known that I, FRANK BITTER, of Iiochester, in the county of Monroe and State of New York, have invented certain new and useful Improvements in Dental Chairs,- and I do hereby declare the following to be a full, clear, and exactdescription of the same, reference being had to the accompanying drawings, forming a part of this specification, and to the reference numerals marked thereon.

My present invention relates to chairs adapted particularly for dental or surgical use and it has for its object to provide a novel head rest adjusting mechanism and also an improved arrangement of parts for holding the chair back in adjusted position relatively to the seat.

To these and other ends the invention consists of certain improvements and combinations of parts, all as will be hereinafter described, the novel features being pointed out in the claims at the end of the specification.

In the drawings: Figure 1 is a rear view of a chair frame showing the back and head rest adjusting mechanism thereon constructed in accordance with my present invention. Fig. 2 is a side elevation of these parts. Fig. 3 is an enlarged central sectional view of the head rest mechanism taken on the line 3 3 of Fig. 1. Fig. 4 is a detail cross sectional view taken on the line 4 1 of Fig. 3.

In illustrating my present invention I have shown a dental or surgical chair 'comprising the main frame or seat 1 which is mounted, as will be understood, upon a suitable base or pedestal part of which is shown and indicated by 2. The chair back comprises the back frame 33, carrying the back rest a and having at its lower end the laterally extending'arms 5, which are pivoted to arms 6 on the frame 1 whereby the back may be rotated from a. vertical to approximately a horizontal position. The head rest is adjustable on the chair back in a vertical direction thereon by means of the slide 7 which constitutes an adjustable support by means of which the head rest may be raised or lowered to accommodate persons of different height, said slide being clamped in guides formed either in the rear of the frame piece 3 or in ways provided in the adjusting bar 8 carrying the back rest 4: and by means of which the latter is posi- Specification of Letters Patent.

Patented Nov. 9, 1915.

Serial No. 697,681.

thus formed is a cylindrical clamping part 14; which is surrounded by the clamping member 15. In the present instance the clamping members 18 and 15 are shown in the form of split compression clamps, having the ears 13 13 and 15 and 15*,which are perforated to receive the clamping bolts 16 and 17. Extending between the clamping members is the connecting member 18, a hollow column of any desired length, the extremities of which are suitably formed to provide bearing surfaces, cooperating with corresponding surfaces formed on the clamping members 13 and15. These surfaces in the present instance are shown as formed by the conical extensions 19 and 20 fitting corresponding recesses provided in one ear of each clamping member. Other forms of bearing surfaces may be used at these points, but I prefer the one shown as it facilitates the locking of the clamping members in an adjustable position on the column, when these are moved or rotated about its axis.

. The bolts 16 and 17 enter the ends of the column and suitable mechanism is employed for moving them longitudinally relatively to each other, simultaneously to open and close the clamping members 13 and 15 and also to secure these in their position of rotary adjustment on the ends of the column. As an illustration of one means of carrying out this feature of my invention I have shown the bolt 16 provided with the inner reduced end 16 formed by cutting away portions at the sides of the bolt. In the edge of the flat web thus formed a recess is cut, the lower edge of which is inclined, forming the cam surface 16. Cooperating with the latter is a similar surface 17 on a plate 17 pivotally connected, as indicated at 17, on the-inner end of the bolt 17. The plate 17 constitutes a cam member which ifmoved relatively to the bolt 16 will cause the latter to be retracted and the bolt 17 similarly moved longitudinally of the column 18. The devices for actuating the cam membercomprise a yoke, havingside pieces 22 and the actuating member 23. They embrace the end 16 of the bolt 16 and the overlapping end of the cam plate 17 a and at its rear end is a set screw/'22 and at its forward end is pivoted the actuating member 23, journaled on the bolt 24 and having the cam face or nose 23 engaging the side of the plate 17 and also provided with a handle 23 by means of which it may be conveniently operated.

One of the two clamping bolts should be provided with means for adjusting the ini- 'tial position of the cooperating parts so that they may be set to prevent lost motion between them when the clamping members are released or unlocked. A simple means of accomplishing this adjustment is to provide the bolt 17 with an adjustable head in the form of a set screw 25 which cooperates with the outer car 15 of the clamping member 15. Rotary movement of the bolt 17 during adjustment of the set screw 25 is prevented by the pin 26 in the ear 15 'Which engages *a slot in said bolt..

A head rest mechanism embodying my present invention is particularly adapted to be applied to dental, surgical or other classes of chairs for supporting the head of the patient in any desired position of adjustment, since the described arrangement of the parts permits of a wide range of movement, either forwardly or rearwardly, vertically or laterally. Another noteworthy feature of the construction is that the desired angular re-' 34 carried by the rearwardly extending lugs, 35 on the seat frame 1. The head 33 is hollow and its upper and lower walls are perforated to form a guide for the rod 30 passing therethrough at one side: of the center of the head, the latter being provided with an opening in its lower walls through which extends the lower laterally projecting end of the foot lever 36 pivoted to the head at 37 and having a nose 38 forming a detent co operating with the notches in the bar 30. The detent is moved in one direction by a coil spring 39 and its pivot 37, is so positioned that upon the drawing of the bar up.- wardly the detent is automatically tripped.

. This arrangement of the parts permits the chair back to be quickly elevated from the horizontal to the vertical position should occasion require, it only being necessary for the operator to depress the treadle 36 when 'he desires to lower the chair back.

I claim as my invention:

1. In a head rest structure the combination with a columnar member, and split clamping members journaled on its ends, one receiving a part on a suitable support and the other engaging a part on a head rest, of bolts I passing through the clamps and extending longitudinally within the member and oper-,

ating devices engaging the inner ends of the bolts for moving theminwardly longitudinally to. close the clamps.

2. The combination with twoclamping members, one adapted to receive a part on a suitable support and the other for engaging a part on a head rest, and a column connecting said members having at its ends bearing surfaces engaging similar surfaces on the! clamping members, of bolts passing through the latter and extending longitudinally in the column, means within. the column for adjusting the bolts relatively toward each other and an actuating member exterior of the column for operating said means. 7

3. The combination with a support and a head rest, both. having clamping parts and two split clamping members cooperating with said parts having parallel perforated ears, one of said ears of each clamp being provided with a bearing-surface, of a tubular member having correspondingbearing surfaces atits ends on which said clamps are journaled, bolts extending through the ears of the clamps and projecting into the tubular member, operating connection between said bolts comprising overlapping parts having cooperating cam surfaces and an operating member for pressing said surfaces together. V

4:. In an adjusting mechanism for head rests in combination with a supported'hoL low member having a bearing surface, an expansible and contractible clamping member journaled on saidsurface and a head rest having a part to be engaged by the clamping member, of a bolt for contracting the clamp and locking it on the bearing surface having its inner end provided with a cam surface" and located within the hollow member, a

cam member separate from the bolt and pivoted within the hollow member-and cooperating with said surface and means for adjusting it to effect longitudinal movementv v of thebolt. r p

5. In an adjusting mechanism forhead rests thecombination with a supported hol-* low member having a 1 bearing surface, a clamping'member journaled on said surface and a head rest havin a part to beengaged by'the clamping member, of a-bolt for op crating the clamp and locking it on the bearing surface having its inner end located within the hollow member and reduced in cross section and provided with a cam surface, a cam member cooperating with the latter to move it inward relatively to the hollow member, a yoke embracing the bolt and cam member and an actuating device on the yoke for moving the cam member relatively to the bolt in a direction to effect its longitudinal movement.

6. In a head rest supporting mechanism, the combination with a support and a head rest both having clamping parts and two separate clamps engaging' said parts, of a hollow connecting member between said clamps, bolts for operating the clamps passing into said member, a cam member pivoted on one of the bolts and overlapping the end of the other bolt, the overlapping parts of the bolt and member being provided with cooperating cam surfaces, a yoke surrounding said parts and means thereon for moving them relatively to cause the cam surfaces to adjust the bolts longitudinally.

7. In a head rest mechanism, the c0mbination with two eXpansible and contractible clamping members and a connecting tubular member, of bolts for operating the clamps extending into the connecting member, operating mechanism extending longitudinally Within the latter for moving said bolts to- Ward each other to contract the clamps, means for adjusting the initial position of one of said bolts and an operating device controlling said mechanism.

8. In a head rest mechanism, the combina tion with two clamping members, a connecting tubular member and operating bolts eX- tending through the clamps and into the connecting member, one of said bolts being provided with a cam surface, of a plate attached to the other bolt and provided with a cam surface adapted to cooperate with the first mentioned surface, a yoke embracing the cam plate and bolt, an adjusting device on the yoke engaging one of said parts and an operating member also carried on the yoke and cooperating with the other part.

FRANK BITTER.

Witnesses:

CHARLES W. FERTIG, RUssELL B. GRIFFITH.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

